/Engine/Source/Runtime/Core/Public/Misc/ExpressionParserTypes.h
Attempt parse out the specified pre-defined string from the current read position (or accumulating into the specified existing token)
[TOptional](API\Runtime\Core\IO\TOptional)< [FStringToken](API\Runtime\Core\Misc\FStringToken) > ParseSymbol ( TCHAR Symbol, [FStringToken](API\Runtime\Core\Misc\FStringToken) * Accumulate ) const